Swift

let date = NSDate() // 任意时间对象
let timestamp = date.timeIntervalSince1970

Go

import (
    "time"
)
t := time.Now() // 任意时间对象
timestamp := t.Unix()

Java

java.util.Date date = new java.util.Date(); // 任意时间对象
long timestamp = date.getTime() / 1000;

C

#include <time.h>
time_t t = time(NULL); // 任意时间对象
long timestamp = (long)t;

JavaScript

const date = new Date(); // 任意时间对象
const timestamp = Math.round(date.getTime() / 1000);

Objective-C

NSDate *date = [NSDate date]; // 任意时间对象
NSTimeInterval timestamp = [date timeIntervalSince1970];

MySQL

SELECT unix_timestamp('2021-06-26 12:00:00') // 任意时间

SQLite

SELECT strftime('%s', '2021-06-26 12:00:00') // 任意时间

Erlang

Datetime = calendar:universal_time(), % 任意时间
Timestamp = calendar:datetime_to_gregorian_seconds(Datetime) - 719528*24*3600.

PHP

<?php
// pure php
$date = new DateTime(); // 任意时间对象
$timestamp = $date->getTimestamp();

Python

import time
from datetime import datetime
date = datetime.now()  # 任意时间对象
timestamp = int(date.timestamp())

Ruby

time = Time.now # 任意时间对象
timestamp = time.to_i

Shell

date -d "2021-06-26 12:00:00" +%s

Groovy

Date date = new Date() // 任意时间对象
long timestamp = (date.time / 1000).longValue()

Lua

date = os.time({year=2021, month=6, day=26, hour=12, min=0, sec=0}) -- 任意时间
timestamp = date

.NET/C#

DateTimeOffset date = DateTimeOffset.Now; // 任意时间对象
long timestamp = date.ToUnixTimeSeconds();

Dart

DateTime date = DateTime.now(); // 任意时间对象
int timestamp = (date.millisecondsSinceEpoch / 1000).truncate();